team-zr1

C4 Corvette owners with model years of '89 to
up to the C5 model may not be aware that anytime there has been a ZF 6 speed failure, due to G.Ms dealings, even if you have a minor internal problem with this trannie, you are forced to either pay G.M $5,000 (plus they kepp you trannie and lose the matching part number ) or pay the freight to ZF Industries, wait about 6 weeks and have the unit rebuilt.
G.M themselves do NO repairs, never allowed dealers to, prevent parts and tools to be sold to 3rd party trannie shops and then force the Corvette owner to pay high sums to get there problems fixed. ZF said to me that G.M axed them in 1995 but holds them to a contract until 2004 and thus cannot do anything in selling parts or tools until then. Consider as in my case ( as in many owners I have talked to ) a simple and cheap part such as a syncro starts to act up. You take it to a dealer and tell them to send the unit to ZF who claims general rebuilt is around $2,000 and you get a one year warranty from them. The dealer refuses claims G.M demands to honor the dealers labor you MUST get the unit from G.M. In sending the unit to Zf directly you would get your unit back and still have a matching ORG part number. In G.Ms fashion, you buy $5,000, they take your unit ( which only has a minor problem ) and give you NOTHING in return for its worth.
The dealer tacks on another $2,000 ( for labor and replacing clutch ) and your stuck with a $7,000 repair bill.
Consider in my case my ZF had only 30,000 miles and only the 3rd gear syncro was acting up, in the end I got stuck with a unit for all I know came out of a '89 when mine is a '94 ZR-1. In the end this rebuilt is in worse condition as mine was. Demanding my trannie back and got an excuse G.M does not know where it is.
Now think of it, for that repair price, would it even be worth the cost if you had a base '98 ?
They game of preventing 3rd party trannie shops from getting parts, is pretty dang low of G.M and is causing many of owenrs vow to never again buy a G.M product.
Consider if you want to maintain the car as to matching numbers and by this game, your prized Corvette has lost its worth because G.M wacked the value by forcing you to lose the Org part number.
In 1993 its been told that the ZF was redesigned. One reason was to cease the rattle base Corvettes had when at idle, the other reason I was told by ZF was to reduce the cost of the unit to give GM higher profits. Also its been said that the re-design of gear teeth angle reduced the torque rate from 450 to 400 ft/lbs. This then means the unit such as mine was being in a 405 plus HP engine means the trannie was now running at its design limit. It seems this may be true since most failures I have heard of have been from late '93s and newer.
I have found no one that when buying a Corvette from G.M was told that if there was a trannie failure of any type, that they the customer would be forced to pay thses repair prices and then G.M themselves or the dealers do not open the trannie for any reasons and thus can claim you were the fault of the failure and void any warranty you mite have when by not even opening the unit can never know not only what is wrong but what the cause was.

Rick93Z07

I've investigated this thoroughly and discovered the same situation. You'e lucky if you don't race your vehicle off-road. I was hoping someone would come to the rescue with a $4K Richmond 6 speed conversion or similar. They sell parts.